Generalizing observations from the lowest common denominator in any work place, at its core this article is very cynical and perhaps wishes everyone would just be happy in their mediocrity.
In most projects, there are minority extra-brilliant people, whose talent/knowledge reflect on the entire outcome/product. So you always need people to handle more complexity. And as some others in the discussion have pointed out, often concepts at a level, become clearer when you grapple the next level of complexity.
Soviet society did not fail because they were better at Maths. It may have happened despite it. The right point to infer about that would be, brilliance in Maths is not a sufficient condition for society as a whole to excel. And that's a moot point, as there are so many other necessary conditions - food/shelter/being-alive/etc - leave aside politics.
Also the article ignores probability as a core life concept, by which you can understand so many things. I use it with my kids all the time.
Another thing which frustrates me recently is my inability to grasp modern physics. Without the relevant understanding of the complex maths, one can only get the vaguest idea, of what they(the physicists) are saying. This creates a huge intellectual gap in society.
Also the knowledge gap has another problem. If it gets too wide, then there will be a very-very few ultra elites who all know what they are saying (perhaps that's already the case, unfortunately). And the rest of us, only take their word on face value. I know one person can't know everything and this is an era of specialization. But still, I think Maths is a fundamental thing. And society would only gain when more number of people are proficient at it.